Harvey™ DLX Stethoscopes from Welch Allyn are designed to allow you to hear cardiac, pulmonary and vascular sounds without relying on difficult ?variable pressure? techniques. The 5079-325 model Harvey DLX is equipped with dual-bore tubing. This means it has two uninterrupted sound channels. The brass chestpieces are weighted to transmit a full range of physical sounds. This model has a chrome-plated pediatric chestpiece with a double head. The binaurals can be rotated and have comfort-sealing ear tips.